The Ukraine situation demonstrates the importance of resolving the Nagorno-Karabakh conflict, according to the U.S. Ambassador to Azerbaijan, Richard Morningstar.

Ambassador Morningstar made the remarks on April 30 in the U.S. capital of Washington, D.C. at a conference titled US-Azerbaijan: Vision for the Future.

He said the events in Ukraine demonstrate the importance of the relationship between Azerbaijan and the U.S.

"Azerbaijan and the United States have to work hard to strengthen and protect the relationship," he stressed.

Morningstar went on to add that the Nagorno-Karabakh conflict creates instability in the region that should not be taken advantage of by any party.

"The presidents of Azerbaijan and Armenia need to work together to take concrete steps to resolve the conflict. It will also be tremendously difficult to accomplish resolution without the full cooperation of Russia. We will see whether that will be forthcoming," Morningstar stressed.

The conflict between the two South Caucasus countries began in 1988 when Armenia made territorial claims against Azerbaijan. As a result of the ensuing war, in 1992 Armenian armed forces occupied 20 percent of Azerbaijan, including the Nagorno-Karabakh region and seven surrounding districts.

The two countries signed a ceasefire agreement in 1994. The co-chairs of the OSCE Minsk Group, Russia, France and the U.S. are currently holding peace negotiations.

Armenia has not yet implemented the U.N. Security Council's four resolutions on the liberation of the Nagorno-Karabakh and the surrounding regions.

A change of power took place in Ukraine on February 22.

The Verkhovna Rada (parliament) of Ukraine ousted President Viktor Yanukovych from the power, changed the constitution and scheduled presidential elections for May 25.

Yanukovych said he was forced to leave Ukraine under the threat of violence, and he remains the legally elected head of state.

A number of provinces in eastern and southern Ukraine, as well as the Crimea did not recognize the legitimacy of the Rada and decided on possibility of holding a referendum on the future fate of the regions.

The vast majority of residents of Crimea - 96 percent - voted to secede from Ukraine and join Russia, in a referendum held March 16.

With the exception of Russia most countries refused to recognize the referendum and its results.

On March 18, Russia and Crimea signed an agreement on Crimea as well as Sevastopol city joining the Russian Federation.